Use Party Healing on 3 or more people in Critical condition.

I feel like your theory is too complicated, but if you have a simple easy-to-understand way to word what you want to say on the main page, you may as well add it. If someone removes it without explanation, you can always ask them for counter-evidence on their user talk page.

I'll try to find easier to understand wording.

I finally realized I did not read the first post carefully enough. I now fully understand the test you were conducting and the kind of extra information you are trying to add. I'm still not sure how to word it in a way that is easily understood for the general wiki reader though. I will think about it as well.

I think it will be good enough to mention in the Training section a line from Healing.
"The skill must recover HP to receive skill training (full HP as well as wounding does not count)."
The requirement is almost the same, so I shall reword it a bit. This should be enough for any confused players who might be trying to train party heal.